Indophenols and leucoindophenols of the azine series



Patented Feb. 7, 1933 UNITED STATES INC., 01 NEW YORK, N. Y., A CORPORATION OF DELAWARE mnornnnonshm) LEUcoIi'moPnanoLs on THE nzmn snares No Drawing. Application filed November 13, 1929, Serial No. 407,007, and in Germany February 14,1027.

My invention relates to new indophenol compounds and the process of preparing same. formula:

OHQNE The; H D tan-n i i X .7 V I I E 1!! wherein A and B stand for hydrogen, alkyl, phenyl or jointly stand-forone of the grouplIlgS H2 CH D and E stand for hydrogen or j oint 1y for one of the groupings CH-,'=CH

the Gs stand for hydrogen or chlorine, and X means i Y a In accordance with the present invention the new compounds are produced by joint oxidation of a compound of. the general formula! ing leuco-compound. Among the different processes which lead to mynew indophenols,

I mention as particularly useful the jointoxidation of these said compounds with a paminophenol in aqueous mineral acid solution by means of an alkali metalbichromate', though in certain cases condensation'with a quinone-halogen-imid or a p-nitroso-phenol might be preferred. f Substantially identical They probably have the general valuable sulfur dyestuffs.

rnrnnnrcn MUTILOF nnnnnrnnnennmnv, nssronon T0 GENERAL Amman woans, 4

indophenolic compounds are however produced when using. the qualified materials. ;f My new compounds are generally light the corresponding dark coloredindophenols.

They produce in the polysulfide; melt very The vfollowing examples will illustrate my invention without limiting it thereto:

' Ewample 1.--19,3 kg. of tetrahydroquinoline (prepared as described in. Ber. d.

The resultingsolutioniscausedto flow quick: 7 a ly into an ice-cold aqueous solution of 29kg.

of sodium dichromate. When the;- oxidation is complete litres of caustic soda (30%) e are added and the solution is reduced by means of sodium sulfide or hydrosulfide until the deep'redcOloration is converted into the light yellow coloration of the leuco-in dophenol. It is then'r'endered vdistinctly acid to Congo with'mineral acid; heated to; 60 C. and allowedto cool. The leucoindophenol of the probable formula cm i a G 'F I g separates as a pale yellowish sandy powder. It is filteredwithsuction and washedgfad vantageously with common salt solution.

a The leuco product is soluble in causticsoda solution first to a colorless solution which then quickly oxidizes in the presence of. air

accompaniedby an intense red-coloration;

In the same manner as descrlbedabove; a

V greyish crystalline powders,soluble in warm -55 deutschen chem. Ges. 16, page/7281) are susproduct ofsimilar -propertieswill be ob tained, when homo-py-tetrahydroquinoline,' the preparation of which is' describediin Berichte der Deutschen chemischen Qesella I schaft 45, page 3376 and 55, page 3824, is used as starting material. The compound obtained has the probable formula:

E wample 2.721.4 kg. of tetrahydroquinal dine (prepared as described in Bel. d. deutschen chem. Ges, 16, page 2467) are dissolved as indicated in Example 1 and oxidizedtogether with 37kg. of the sulfate of 2:6- ,dichloro-para-aminophenol, in the manner disclosed in the foregoing example, reduced and separated. The behaviour of the leuco indophenol of the probable formula o1 V QHQ-Qm 1 towards caustic soda is analogous to that of Example 1. f V

In an analogous manner cc-PhGIlYltGtIflhY- droquinoline (described in Berichte der deutschen chemischen Gesellschait 55, page 37 85), yields the compound on V I kHa (tnoni ([11 V L CH 0H NH x135: I

and B-phenyltetrahydroquinoline (-Berichte der deutschen chemischen Gesellschaft '55, 3790) the leucoindophenol.

O on NH-- 1 4111: I

These compounds have similar properties as the product of Example 1.

. With 2-propyl-tetrahydroquinoline' and pamidophenol the leucoindophenol of the probable formula:

JJH-OaH- NH is obtained in an analogous manner. The mentioned 2-propyl-tetrahydroquinoline is described in Berichte der deutschen chemischen' Gesellschaft 57, page 385.

Example 3.-21.4 kg. tetrahydrolepidine (Berichte der deutschen chemischen- Gesell- 'schaft 56,page 1341) aredissolved as indicated in Example land oxidized together with 15.8 kg. of p-a' nidophenoh'in the manner disclosed in Example 1, reduced andsep- 'arated. i

violet coloration, j Another product of The behaviour of the leuco indophenol of the probable formula:

GHQ-NHU EH2 NH/ H2 indophenol the probable 1 GH:--0H{ forms alight yellow powder, it is soluble in aqueous caustic soda first to a colorless solution which then quickly oxidizes in the'presence of air'accompanied by an intense red similar properties is obtained when tetrahydro-a-naphthoquinoline (Berichte der deutschen chemischen Gesellschalt 24, page 2475) is used as starting material. This indophenol has the probable formula: a

GHQ-NB (gHzilr v The indophenol of the probable formula:

is obtained when 2-methyl-tetrahydro-anaphthoquinoline (described in Journ. chem.

Soc.,London, 1926, page 2247) is used as starting material. The preparation of this indophenol is identical with that of theforegoing example and the indophenol has also similar properties as the product described above.

Example 5. 27 kg. of octo-hydro-a-cridine (Journ, chem. Soc., London, 127, page438) are" dissolved as described in Example 1 and oxidized in the manner disclosed in Example 1 together with 16 kg. of p-aminophenol, reduced and separated. p

'lihe leuco indophenol of the probable formu a:

CH3 forms a yellow brown powder. It is soluble in aqueous caustic soda first to a colorless solution, which is speedily oxidized in the r red-Violet coloration.

In an analogous manner 2.3-trimethylenetetrahydroquinoline (prepared as described in Berichte'der deutschen chemischen Gesellschalt 56, 1349) and octa-hydroheptaquinoline (J ourn. chem. Soc., London, 1928, page 2583) furnish the leucoindophenols of the probable formulas NH on,

' OH NH/ onhom I claim:

1. As new products, the compounds of the probable general formula 1 G OHQNH :0

OHONH E AIR: 7 NH/ 7 being a light greyish crystalline powder, sol- E H-A tire-B uble in hot water, alcohol and mineral acids and sparingly soluble in salt solutions, forming colorless solutions with aqueous alkalies,

5 in which the leuco-indophenol is easily oxipresence of air accompanied by an intense I hydrogen or chlorine.

dized, to the corresponding dark colored indophenol, and producingin the polysulfide melt a Very valuable sulfur dyestuif.

3. As new products, the compounds of the" probable general formula:

wherein A stands for hydrogen and B stands for hydrogen, alkyl or phenyl, or A and B jointly stand for one of the groupings CH' CH2 CH2 CH2 01' f CH2 CH2 CH2 CH2 3 D and E stand for hydrogen or jointlyfor the grouping CH=CH CH=CH- or CH CH CH CH and the Gs stand for 4. As a'new product, the compound of the probable formula:

said compound formingcolorless solutions with aqueous alkalies in which the leuco-indophenol is easily oxidized to the corresponding dark colored indophenol, and yielding in thefipolysulfide melt a Valuable sulfur dyestu 5. As a new product, the compound ofthe probable formula:

H1 I NH said compound'forming colorless solutions.

with aqueous alkalies in which the leuco-in dophenol is quickly oxidized to the corresponding dark colored indophenol displaying an intense-red-violetcoloration in the aqueous alkaline solution, and yielding in the polysulfide melt a valuablesulfur dyestufi.

FRIEDRICH MUTH. 

